Solved RJ45 jack used for RJ11

My goal was to use RJ45 Ethernet jacks also for RJ11 Telephone connections.I noticed that my builder had connected all 8 conductors (4 pairs) using the same straight colors for the RJ11, telephone connections, but had inverted the Blue and Orange pairs positions for the initially planned RJ45, ethernet connections.

Any reason why he would have done this?

When I wired the other end of the cables I was assuming that all jacks in the house were wired in the same way, so I installed plugs at the other end of the cables using this same convention. However, I was surprised when a jack intended for telephone use did not work for ethernet when I tried plugging in all my switches and routers. I later realised that the orange and blue pairs had been interchanged for all intended ethernet use jacks.

Is it possible to use the same connections (using the matching color codes) straight, for the RJ11 as well as RJ45 jacks?

Can someone point me to a wiring scheme where I can achieve this goal of using the same jack for ethernet as well as a telephone line, assuming that the other end of the cable connected to the jack is plugged into the correct hardware?

Sorry I took so long to reply again. I was out of town on a hunting trip (and a very successful one I might add) and this is my first day back after the trip.

Ok, I had an opportunity today to test out whether or not we can use an RJ-45 keystone with an RJ-11 plug from a telephone. You'll be happy to know it worked.

In a nutshell, we had to move a printer/fax machine from one office to another. In times past, we would remove the cable from the back of the patch panel and then punch it into the bix block. This time, we ran a regular network cable from the port on the patch panel to the bix block and cut off the RJ-45 at that end and punched into the bix. We left the RJ-45 keystone in the faceplate at the other end to see if it would indeed work and as I stated above, it did. We tested by plugging an analog phone set into the RJ-45. I not only got dial tone, but was able to dial my cell phone to verify a working connection as well as the correct phone number.

NOTE: This was an analog fax line. I doubt it makes any difference if it were a digital or analog phone line as it will only be using the one pair either way.

Since this worked. Were we ever to need that back as a data line, we would unplug the jumper cable from the patch panel port (other end punched to the bix block) and then just run a patch cable from switch to patch panel port and it would work for data.

Why are you mixing RJ11 and RJ45. I cannot imagine any situation where it would be necessary. Because the two plugs are designed for different purposes you are not going to find any standard wiring diagram. If you insist on mixing RJ45 and RJ11 then you are going to have to work it out yourself.

An RJ11 plug is smaller than an RJ45 although it will fit in an RJ45 socket. RJ11 has six connectors but normally only four are used while RJ45 has eight although normally only four are used.

Using RJ45 jacks for phones is very common in the business world and the wiring standard for it is USOC. However, T568A is probably used more often because besides being an Ethernet wiring standard, it also complies with 2pr USOC (2 line phone). T568B can also be used for 2 line phones, but the color code does not comply with the 2p USOC standard.

Stuart, I looked at your link. I'm just curious about something...WHAT was this guy thinking when he was saying how to remember the combinations for the Telephone color codes? Two Holidays. Christmas and Halloween. What in the world does the combination of black and yellow have to do with Halloween? LOL I realize you may not know the answer, but his logic(?) was lost on me.

The reason I was trying to mix the 2 is so that I can use a single jack that works for both phone and ethernet.

At the other end of the cable connected to the jack, I have terminated it with an RJ45 plug.

When I plug this into a phone distribution jack, I want it to work as a phone and when I plug it into a Gigabit switch, I want it to work as an ethernet outlet.

Since the RJ11 plug fits into an RJ45 jack and uses only some of the wires, in theory I should be able to switch/route 2 phone conductors into the right spots and get phone service. The phone distribution panel I am using supports rearranging 4 pairs of conductors into various jacks using different permutations (There is 1 incoming 110 style punchdown and 24 RJ45 distribution outgoing jacks that are connected to the incoming 4 pairs in various "order").

Some answers to questions that would help me solve this wiring problem are:

1) Which is the pair of conductors (or color code) used by an RJ11 plug, plugged into an RJ45 jack?2) In multiline phones, what is the "order" of lines.... i.e. line 1 uses which color, line 2 uses which color, etc?3) My same original question on why would a builder wire an ethernet jack to reverse the blue and orange conductors?4) Additionally, I was looking for an RJ45 adapter that would let me change the order of the conductors. Ideally, something that would use some switches to let me configure any random cross network without having to rewire anything. Does anyone know where I can possibly find such a device? I tried doing a Google search but couldn't find anything.

>> "The reason I was trying to mix the 2 is so that I can use a single jack that works for both phone and ethernet."

If you mean that you want a single jack to be used simultaneously for phone and Ethernet, then that's a bad idea. You should have separate dedicated jacks.

>> "At the other end of the cable connected to the jack, I have terminated it with an RJ45 plug."

Wrong. Both ends should be terminated at a jack (wall jack or patch panel) and patch cables is used to connect from the jack to the network device.

>> "When I plug this into a phone distribution jack, I want it to work as a phone and when I plug it into a Gigabit switch, I want it to work as an ethernet outlet."

So, when you want to use the phone, you plug it into a phone distribution box and when you want to use your computer, you move it into a switch. That's a really bad approach. What happens when you want/need to do both at the same time? Cable is cheap, just make 2 runs (1 for network and 1 for phone).

>> "1) Which is the pair of conductors (or color code) used by an RJ11 plug, plugged into an RJ45 jack?"

See the link in my previous post.

>> "2) In multiline phones, what is the "order" of lines.... i.e. line 1 uses which color, line 2 uses which color, etc?"

See my answer to your Q1.

>> "3) My same original question on why would a builder wire an ethernet jack to reverse the blue and orange conductors?"

They goofed, the orange and green pairs are the ones that get swapped to create a cross over connection.

>>"4) Additionally, I was looking for an RJ45 adapter that would let me change the order of the conductors. Ideally, something that would use some switches to let me configure any random cross network without having to rewire anything."

That's a really bad idea and I've never seen and I doubt that you'll be able to find such an adapter. Just run the required cables and be done with it.

They goofed, the orange and green pairs are the ones that get swapped to create a cross over connection.

Agreed. Their scheme isn't compliant with either standard (A or B) and to me makes no sense whatsoever. If you contracted someone to do the cabling for you, call them back and insist they send someone who know's the standards and repunches all of them with one or the other....this should be done at their expense. Alternatively, you could do it yourself.

Additionally, I was looking for an RJ45 adapter that would let me change the order of the conductors. Ideally, something that would use some switches to let me configure any random cross network without having to rewire anything."

I'm not even sure what you're trying to get at with this idea as it makes no sense to me. Are you saying you're trying to avoid having to make or buy a crossover cable??? I can make a cable, crossover or straight through, in under 2 minutes.....granted, I've made more than you can shake a stick at, just like I've pulled, punched and tested miles and miles of cabling over the years.......regardless, it doesn't take that much time to make a cable and premade crossover's are pretty cheap. Stuarts correct, there is no such adapter.

As for using phones in the same RJ-45 as a network, it probably can be done. However, you're left with two problems. One, how to connect your phone line at the other end, and two, you can't use the jack in the wall outlet for data and voice. It's a one or the other type of situation. If you punch the Keystone for a phone, in order to use it for data, you'd then have to repunch it for data.

Lately we've been doing something similar ourselves to keep future options open for VoIP phones. However, make note of this, we use RJ-11 keystones at the wall outlets. But those cables do terminate in a patch panel and are then jumpered with a cable that plugs into the PP with an RJ-45 and then is either punched into a bix block or, goes to a special (read: expensive) bix bock that has RJ-45 ends in it that are jumpered from the actual bix. This means you can just use a Cat5/6 cable with RJ-45's at both ends.

HOWEVER, the main point being. For digital/analog connections we use RJ-11 keystones at the outlet. You could use an RJ-45, but you'd never be able to use it for a network (data) connection without repunching the end at the wall outlet as the two (data/phone) are incompatible. There is no "cross standard".

Granted, Keystones aren't cheap cheap, but we found a supplier that sells them to use for under $2.00/ea (CDN).

In the end, my suggestion/recommendation is, use RJ-11 keystones at the outlet for phones.

Sorry I took so long to reply again. I was out of town on a hunting trip (and a very successful one I might add) and this is my first day back after the trip.

Ok, I had an opportunity today to test out whether or not we can use an RJ-45 keystone with an RJ-11 plug from a telephone. You'll be happy to know it worked.

In a nutshell, we had to move a printer/fax machine from one office to another. In times past, we would remove the cable from the back of the patch panel and then punch it into the bix block. This time, we ran a regular network cable from the port on the patch panel to the bix block and cut off the RJ-45 at that end and punched into the bix. We left the RJ-45 keystone in the faceplate at the other end to see if it would indeed work and as I stated above, it did. We tested by plugging an analog phone set into the RJ-45. I not only got dial tone, but was able to dial my cell phone to verify a working connection as well as the correct phone number.

NOTE: This was an analog fax line. I doubt it makes any difference if it were a digital or analog phone line as it will only be using the one pair either way.

Since this worked. Were we ever to need that back as a data line, we would unplug the jumper cable from the patch panel port (other end punched to the bix block) and then just run a patch cable from switch to patch panel port and it would work for data.

Jennifer, in case you are still following this thread.I think the guy has his Halloween colors confused a little as they are black and orange not black and yellow.The Celtics are given credit for beginning the holiday as the festival of the harvest, the color of autumn is used. Orange, being the most prevalent autumn color and it comes from the color of pumpkins and leaves.Death is usually associated with darkness and absence of light signified by the color black. More than you ever wanted to know, I am sure.

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